docs: def get_category_files_from_api(category_name):
      """Yield the file names of a category by querying the MediaWiki API."""
      import mwclient
      site = mwclient.Site('commons.wikimedia.org')
      category = site.Categories[category_name]
      return (x.page_title.encode('utf-8')
              for x in category.members(namespace=6))